CN113221061B - Parabolic substrate resonant curved surface bulldozer blade and soil contact curved surface setting method - Google Patents
Parabolic substrate resonant curved surface bulldozer blade and soil contact curved surface setting method Download PDFInfo
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- CN113221061B CN113221061B CN202110471791.6A CN202110471791A CN113221061B CN 113221061 B CN113221061 B CN 113221061B CN 202110471791 A CN202110471791 A CN 202110471791A CN 113221061 B CN113221061 B CN 113221061B
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- 239000002689 soil Substances 0.000 title claims abstract description 93
- 239000000758 substrate Substances 0.000 title claims abstract description 15
- 238000000034 method Methods 0.000 title claims abstract description 14
- 238000005265 energy consumption Methods 0.000 abstract description 5
- 239000002245 particle Substances 0.000 description 8
- 238000010586 diagram Methods 0.000 description 4
- 238000004088 simulation Methods 0.000 description 4
- 238000001228 spectrum Methods 0.000 description 4
- 238000003795 desorption Methods 0.000 description 2
- 230000005284 excitation Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
- 239000000295 fuel oil Substances 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 239000011664 nicotinic acid Substances 0.000 description 1
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F17/00—Digital computing or data processing equipment or methods, specially adapted for specific functions
- G06F17/10—Complex mathematical operations
- G06F17/11—Complex mathematical operations for solving equations, e.g. nonlinear equations, general mathematical optimization problems
- G06F17/12—Simultaneous equations, e.g. systems of linear equations
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- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02F—DREDGING; SOIL-SHIFTING
- E02F3/00—Dredgers; Soil-shifting machines
- E02F3/04—Dredgers; Soil-shifting machines mechanically-driven
- E02F3/76—Graders, bulldozers, or the like with scraper plates or ploughshare-like elements; Levelling scarifying devices
- E02F3/80—Component parts
- E02F3/815—Blades; Levelling or scarifying tools
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Abstract
The invention relates to a parabolic substrate resonance type curved bulldozer and a method for setting a soil-touching curved surface, wherein the bulldozer is provided with the soil-touching curved surface, an upper end surface, a lower end surface and a rear end surface, the outline of the soil-touching curved surface is a complex curve, the complex curve is formed by superposing a parabolic curve and a sine function curve, and the equation of the complex curve is a parameter equation: Wherein the value range of t is 0-100, the point corresponding to the value of t is positioned at the bottom end of the soil contact curved surface when the value of t is 0, the point corresponding to the value of t is positioned at the top end of the soil contact curved surface when the value of t is 100, A is the amplitude of the sine function curve, f 0 is the first-order natural frequency of soil, and u is the working speed of a bulldozer plate; the soil contact curved surface is obtained by scanning a contour line along a straight line, and the contour line is obtained by taking a parabola as a base line through rotation and superposing a sine function curve on the base line. The invention can effectively reduce the adhesion and working resistance of the soil contact curved surface, reduce the energy consumption loss of the bulldozer and improve the working efficiency.
Description
Technical Field
The invention belongs to the technical field of engineering machinery, and particularly relates to a parabolic substrate resonant curved bulldozer plate used on a bulldozer and a setting method of a soil contact curved surface.
Background
Bulldozers are widely applied to various fields such as urban construction and mining, the guard amount of bulldozers in China is about 10 ten thousand by 2020, the annual consumption of fuel oil is not less than 300 ten thousand tons, and the reduction of the working resistance of the bulldozers is significant for energy conservation and emission reduction. The bulldozer is used as a direct working part of the bulldozer, the power consumed in working accounts for about 40% of the whole bulldozer, the geometric shape of the soil contact curved surface of the bulldozer directly influences the desorption resistance reduction performance of the bulldozer, and the reasonable structure of the soil contact curved surface of the bulldozer can reduce the power consumption of the bulldozer. The conventional drag reduction methods for numerous soil-contacting components can reduce the working resistance to some extent, but also have many limitations and additional energy consumption.
When the automobile runs over an uneven road surface, the tires are excited by the road surface spectrum to vibrate the automobile body, because the time frequency f is input to the automobile when the automobile runs over the road surface spectrum of the spatial frequency n at a certain speed u, and f=un. The road spectrum is introduced onto the soil contact surface of the bulldozer plate by the phenomenon, so that the soil particles have ripples with a certain spatial frequency, when the soil particles slide through the soil contact curved surface of the bulldozer plate, the soil particles have a certain vibration frequency by being excited by the road spectrum on the soil contact surface, and when the frequency is close to the first-order natural frequency of the soil, the resonance phenomenon occurs, so that the working resistance can be reduced without additional energy consumption, and the soil adhesion is lightened.
Disclosure of Invention
The invention aims to solve the problems of high working resistance and high power consumption of a bulldozer, and provides a parabolic substrate resonant curved bulldozer, which can effectively reduce the adhesion and working resistance of a soil contact curved surface, reduce the energy consumption loss of the bulldozer and improve the working efficiency.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: a parabolic substrate resonance type curved surface bulldozer is provided with a soil contact curved surface, an upper end surface, a lower end surface and a rear end surface, wherein the contour line of the soil contact curved surface is a complex curve which is formed by superposing a parabolic curve and a sine function curve, and the equation of the complex curve is a parameter equation:
Wherein the value range of t is 0-100, the point corresponding to the value of t is positioned at the bottom end of the soil contact curved surface when the value of t is 0, the point corresponding to the value of t is positioned at the top end of the soil contact curved surface when the value of t is 100, A is the amplitude of the sine function curve, f 0 is the first-order natural vibration frequency of soil, and u is the working speed of a bulldozer blade.
The equation of the parabola is y=0.0128 x 2 -2.4404x, and the value range of x is 0-100.
When the parabola and the sine function curve are overlapped, the parabola rotates anticlockwise in the plane of the parabola, then the parabola is overlapped with the sine function curve, and after the parabola rotates, the angle between the connecting lines of the two ends of the parabola and the x-axis is 78 degrees.
The included angle between the lower end face and the horizontal plane is 30 degrees.
A setting method of a soil contact curved surface of a bulldozer comprises the following steps: (1) Selecting a parabolic curve equation of y=0.0128 x 2 -2.4404x, wherein the value range of x is 0-100, rotating the parabolic curve anticlockwise in the plane of the parabolic curve, and obtaining a base line by connecting lines at two ends of the parabolic curve and an x-axis clamping angle of 78 degrees after rotating the parabolic curve; (2) The equation is obtained according to the first-order natural frequency f 0 of the soil and the working speed u of the bulldozer bladeWherein a is the amplitude of the sinusoidal curve; (3) Superposing the base line obtained in the step (1) and the sine function curve obtained in the step (2) to obtain a contour line of the soil contact curved surface of the bulldozer, wherein an equation of the contour line is a parameter equation: /(I)Wherein the value range of t is 0-100; (4) And (3) scanning the contour line obtained in the step (3) along a straight line to obtain the soil contact curved surface of the bulldozer.
The first order natural frequency f 0 of the soil is the result measured by a laboratory hammer method soil trough test.
And when the first-order natural frequency test result f 0 of the soil is 29Hz, the working speed u of the bulldozer is 0.16m/s, and the amplitude A is 2mm, the corresponding sine function curve equation is y=2sin (1.138 x).
The principle of the invention is as follows: when the soil slides across the soil-touching curved surface, excitation of the soil-touching curved surface enables soil particles to have certain vibration frequency, resonance phenomenon occurs when the frequency is close to first-order natural frequency of the soil, and at the moment, working resistance of the bulldozer can be reduced without additional energy consumption, and soil adhesion is lightened.
The parabola is a curve with resistance reduction capability, the sine function curve is generated according to the first-order natural frequency of given soil, the soil touching curved surface is endowed with a spatial frequency n, and when the bulldozer plate works at a speed u, soil particles sliding over the soil touching curved surface of the bulldozer plate are excited by the soil touching curved surface, and vibration with a frequency f can be generated. The vibration frequency f=un of the soil particles, and when the working speed u is fixed and the space frequency n of the soil contact curved surface is changed through designing a sine function curve so that the frequency f is close to the first-order natural frequency of the soil, the soil particles sliding through the soil contact curved surface of the bulldozer plate can generate resonance phenomenon; when the space frequency n of the soil contact curved surface of the bulldozer is fixed and the frequency f is close to the first-order natural frequency of the soil by adjusting the speed u of the bulldozer, the resonance phenomenon of soil particles sliding across the soil contact curved surface of the bulldozer can also occur.
The beneficial effects of the invention are as follows: firstly, the bulldozer blade is based on the characteristic of resonance drag reduction of soil, and can change the motion state of the soil when the soil contacts with a soil contact curved surface when being applied to the design of the bulldozer blade, and the resonance phenomenon occurs to enable the soil to be quickly loosened, so that the working resistance of the bulldozer is reduced, the desorption drag reduction performance of the bulldozer is improved, and compared with the traditional parabolic bulldozer blade, the drag reduction performance is improved by about 17%.
Secondly, the bulldozer blade has strong adaptability, can design a corresponding bulldozer blade according to the first-order natural frequency of the soil in different areas, and better plays a role in resonance drag reduction; meanwhile, when the designed bulldozer blade changes the working site, the excitation frequency of the bulldozer blade can be close to the first-order natural frequency of the new site again through speed adjustment, so that the resonance drag reduction effect is exerted.
Thirdly, the bulldozer blade of the invention has universality, can be scaled in an equal ratio, and can be produced to be suitable for large, medium and small bulldozers.
Drawings
FIG. 1 is a schematic diagram of the structure of the present invention;
FIG. 2 is a side view of the present invention in a coordinate system;
FIG. 3 is a parabolic graph of the present invention as a base line;
FIG. 4 is a graph of the parabolic rotation of FIG. 3 before and after rotation;
FIG. 5 is a graph of a sine function according to the present invention;
FIG. 6 is a contour diagram of a curved surface for soil contact according to the present invention;
FIG. 7 is a graph showing the comparison of the working resistance of a simulation test of a parabolic substrate resonant type bulldozer blade according to the present invention after overlapping sine function curves of different frequencies and amplitudes;
FIG. 8 is a graphical representation of the comparative operating resistance of a simulation test of a parabolic substrate resonant blade in accordance with the present invention and a conventional parabolic blade;
the marks in the figure: 1. soil contact curved surface 2, up end, 3, down end, 4, back end.
Detailed Description
The invention is described in further detail below with reference to the drawings and examples, which are not intended to be limiting.
Referring to the drawing, a parabolic substrate resonance type curved surface bulldozer is provided with a soil contact curved surface 1, an upper end surface 2, a lower end surface 3 and a rear end surface 4, wherein the soil contact curved surface 1 is arranged opposite to the rear end surface 4, the upper end surface 2 is arranged between the top end of the soil contact curved surface 1 and the rear end surface 4, the lower end surface 3 is arranged between the bottom ends of the soil contact curved surface 1, the upper end surface 2 is horizontal, an included angle between the lower end surface 3 and the horizontal plane is 30 degrees during operation, the contour line of the soil contact curved surface 1 is a complex curve, and the equation of the complex curve is a parameter equation:
Wherein, the value range of t is 0-100, the point corresponding to the value of t is positioned at the bottom end of the soil contact curved surface 1 when the value of t is 0, and the point corresponding to the value of t is positioned at the top end of the soil contact curved surface 1 when the value of t is 100.
The contour line of the soil-touching curved surface 1 is obtained by taking a parabola as a base line through rotation, and superposing a sine function curve on the base line, wherein the parabola is fitted by a bionic curve with good drag reduction capability, the sine function curve is generated according to the first-order natural frequency of given soil, and the first-order natural frequency of the soil can be measured by a hammering method.
The parabolic equation is that y=0.0128 x 2 -2.4404x, the value range of x is 0-100, the parabolic curve graph is shown in fig. 3, the curve graph shown in fig. 3 is rotated anticlockwise in the plane to obtain a base line for overlapping with a sine function curve, after rotation, the clamp angle between the connecting lines at two ends of the curve and the x axis is 78 degrees, and the curve graph before and after rotation is shown in fig. 4.
The generation method of the sine function curve comprises the following steps: the standard formula of the sine function is y=Asin (ωx), and the equation is obtained according to the first-order natural frequency f 0 of the soil and the working speed u of the bulldozer bladeWherein a is the amplitude of the sinusoidal curve. Specifically, the amplitude A=2 mm is obtained empirically, the first-order natural frequency f 0 =29 Hz of the soil in the soil tank is measured, and the speed u of the soil tank trolley is=0.16 m/s, namely the working speed of the bulldozer blade. So the spatial frequency n=f 0/u＝0.181mm-1, the wavelength λ=1/n= 5.524mm, the angular frequency ω=2pi/λ=1.138 rad/mm, a sinusoidal function formula y=2sin (1.138 x) can be obtained, the graph of which is shown in fig. 5.
As can be seen from the parabolic and sinusoidal methods of obtaining the soil first order natural frequency f 0 in the working area, since the spatial frequency n is fixed for the blade, it is necessary to readjust the blade's working speed u according to n=f 0/u to allow the soil to resonate as it slides over the curved surface of the ground.
And superposing the rotated parabola and the obtained sine function curve to obtain the contour line of the soil-contact curved surface, as shown in fig. 6. The "superposition" refers to that for any x value, the y value on the parabola is added with the y value of the sine function curve to obtain the y value of the contour line of the curved surface of the earth. Then the curve is scanned along a straight line according to the graph shown in fig. 6 to obtain the soil contact curved surface of the bulldozer blade.
Fig. 7 shows a simulation test operation resistance diagram of a parabolic substrate resonant type bulldozer and a conventional parabolic type bulldozer designed by superimposing sine function curves with different frequencies and same amplitude under the same soil condition and the same operation depth and operation speed, and a single degree of freedom amplitude-frequency characteristic curve (black line curve in the figure) is added as a comparison reference, it can be seen that the resistance of the parabolic substrate resonant type bulldozer under different frequencies is lower than that of the conventional parabolic type bulldozer, the resistance line diagram is in a concave shape, the design frequency of the parabolic substrate resonant type bulldozer is closer to the first-order natural frequency f 0 of soil, the working resistance is reduced, otherwise, the design frequency is increased, and the bulldozer with the first-order natural frequency is closer to the soil can be considered to have resonance phenomenon with the soil in the front part range during bulldozer. The amplitude-frequency characteristic curve is in a convex shape, in the amplitude-frequency characteristic curve, when the frequency is closer to the first-order natural frequency of the soil, the response is stronger, and conversely, the response is weaker, and the amplitude-frequency characteristic curve also corresponds to the first-order natural frequency of the soil, so that a theoretical basis is provided.
Fig. 8 is a graph showing the comparison of the working resistance of the parabolic substrate resonant type bulldozer with the design frequency of 29Hz and the conventional parabolic type bulldozer in the simulation test under the same soil condition, the same working depth and the same working speed, and it can be seen from the graph that the working resistance of the parabolic substrate resonant type bulldozer according to the present invention is reduced by about 17% compared with the conventional parabolic type bulldozer.
The above embodiments are only for illustrating the technical solution of the present invention and not for limiting it, and it should be understood by those skilled in the art that modifications and equivalents may be made to the specific embodiments of the present invention with reference to the above embodiments, and any modifications and equivalents not departing from the spirit and scope of the present invention are within the scope of the claims appended hereto.
Claims (4)
1. A parabolic substrate resonance type curved surface bulldozer plate is provided with a soil contact curved surface, an upper end surface, a lower end surface and a rear end surface, and is characterized in that the contour line of the soil contact curved surface is a complex curve, the complex curve is formed by superposing a parabolic curve and a sinusoidal curve, and the equation of the complex curve is a parameter equation:
x＝-0.0102t2+1.3373t
Wherein the value range of t is 0-100, the point corresponding to the value of t is positioned at the bottom end of the soil contact curved surface when the value of t is 0, the point corresponding to the value of t is positioned at the top end of the soil contact curved surface when the value of t is 100, A is the amplitude of the sine function curve, f 0 is the first-order natural vibration frequency of soil, and u is the working speed of a bulldozer plate;
the equation of the parabola is y=0.0128 x 2 -2.4404x, and the value range of x is 0-100; when the parabola and the sine function curve are overlapped, firstly, the parabola rotates anticlockwise in the plane of the parabola and then is overlapped with the sine function curve, and after the parabola rotates, the clip angle between the connecting lines of the two ends of the parabola and the x-axis is 78 degrees;
the included angle between the lower end face and the horizontal plane is 30 degrees.
2. The setting method of the soil contact curved surface of the bulldozer blade is characterized by comprising the following steps: (1) Selecting a parabolic curve equation of y=0.0128 x 2 -2.4404x, wherein the value range of x is 0-100, rotating the parabolic curve anticlockwise in the plane of the parabolic curve, and obtaining a base line by connecting lines at two ends of the parabolic curve and an x-axis clamping angle of 78 degrees after rotating the parabolic curve; (2) The equation is obtained according to the first-order natural vibration frequency f 0 of the soil and the working speed u of the bulldozer bladeWherein a is the amplitude of the sinusoidal curve; (3) Superposing the base line obtained in the step (1) and the sine function curve obtained in the step (2) to obtain a contour line of the soil contact curved surface of the bulldozer, wherein an equation of the contour line is a parameter equation: /(I)Wherein the value range of t is 0-100; (4) And (3) scanning the contour line obtained in the step (3) along a straight line to obtain the soil contact curved surface of the bulldozer.
3. The method for setting a soil contact curved surface of a bulldozer according to claim 2, in which said first-order natural frequency f 0 of the soil is a result measured by a laboratory hammering method soil slot test.
4. A method for setting a curved surface of a bulldozer according to claim 2 or 3, in which when the first-order natural frequency test result f 0 =29 Hz of the soil, the working speed u=0.16 m/s of the bulldozer, and the amplitude a=2 mm, the corresponding sine function curve is y=2 sin (1.138 x).
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| WO2007032191A1 (en) * | 2005-09-14 | 2007-03-22 | Komatsu Ltd. | Blade device for working machine and working machine mounted with the same |
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- 2021-04-29 CN CN202110471791.6A patent/CN113221061B/en active Active
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| WO2007032191A1 (en) * | 2005-09-14 | 2007-03-22 | Komatsu Ltd. | Blade device for working machine and working machine mounted with the same |
| CN101258793A (en) * | 2008-04-24 | 2008-09-10 | 吉林大学 | Bionic drag reduction stubbling knife and design method thereof |
| WO2018165999A1 (en) * | 2017-03-16 | 2018-09-20 | 东北大学 | Fiber reinforced composite material parameter identifying method based on laser nondestructive scanning, and device |
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